Mom, is my Car Safe to Drive?

Our oldest daughter called this week. “Mom, my brake light is on.” Our 23 year old daughter was calling me from Newport, Florida. She was heading to St. Augustine for a little sight-seeing and was driving a rental car, a Nissan Sentra to be exact. “What do I do?” Now, my daughter is no dummy. She is an officer in the Coast Guard, happening to be ‘at liberty,’ military lingo for ‘having time off.’

“Pull over, and I’ll tell you how to check the brake fluid.”

I explained to her that the brake light on the dashboard comes on when it senses low brake fluid. A computer sensor on the master cylinder ‘reports’ when the fluid reaches a minimally acceptable level. While the light shouldn’t be disregarded, it doesn’t always mean that the driver is in imminent danger of experiencing brake failure. It does mean stop, check and take care of it.

After Laura figured out how to open the hood, she found the brake fluid reservoir—often it’s close to the firewall. She opened the cap and saw that the fluid level read minimum. Well, she had her answer. Slightly low on fluid, but not in danger. What we didn’t know was why.

There are multiple explanations. The car had 12,000 miles, fairly new for most car owners, but that’s considered “old” in the rental world. The vehicle could have a slow leak either coming from the master cylinder or from a wheel cylinder. Another possibility is that the car had been poorly maintained and over time, the brake pads wore out. This would cause more brake fluid to flow toward the calipers and reduce fluid in the reservoir.

When Laura called me back and told me the fluid level, I said, “What’s also important is how the brake pedal feels when it’s pressed. How’re the brakes working?”

That was what she wanted to hear. When a dashboard light comes on, all of us are naturally concerned because we don’t know whether it’s safe to continue driving.

“Mom, one last question, how will I know if I’m developing a brake problem?”

My advice to her was to watch for puddles on the ground near the tires or under the hood. Check the fluid once more when she stopped for gas and tell the rental car agent when she gets back.

If Laura had said that her brake pedal had been mushy or acting funny in any way that would be a major safety issue. Mushy brake pedals mean brake failure is imminent! If YOU ever experience this, stop driving. You are a road hazard! It’s possible that a mushy pedal will not be accompanied by a brake warning light, but usually, it will.

Without a technician to check Laura’s Nissan, we could not know why the fluid was low, but we knew that she able to stop the car safely and that was what mattered.